Refrigerating apparatus



Feb. .20, 1940- c. E. WARING REFRI GERAT II IG APPARATUS Filed Aug. 13, 1937 16 2 /-1 I 2 F4 Y //4-\ /2- k vzf iwmwwm 7 INVENTOR. C4642; 8 Wale/4'9.

WMMQ,

HIS ATTORNEY 5.

Patented Feb. 20, 1940 UNITED STATES PATENT OFFICE 2,191,263 armor-ammo APPARATUS Charles E. Waring, Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio., a corporation of Delaware Application August 13, 1937, Serial No. 158,990

8 Claims.

I am aware that others have provided a coating over the walls of ice trays and grid structures therefor to render these walls and structures water repellent to prevent bonding of ice mereto. However, none of the prior coatings have been practical due to the expensive methods of applying the coatings to the ice trays or grids and these prior coatings have not been entirely satisfactory due to the fact that the prior coatings are-not permanent in the true meaning of permanency. My invention is therefore directed; to the provision of an improved coating material to be applied to metal ice trays and grids therefor.

An object of my invention is to provide an improved ice :tray and grid structure therefor so as to facilitate the removal of ice blocks therefrom. I 1

Another object of my invention is to coat the walls of a metal tray and metal grid structure therefor with an improved coating material which is highly polar, of low cost and can be readily applied to the walls with a minimum of trouble to thereby render the walls more permanent in water repellent characteristics to prevent so bonding of ice 'thereto.

In'carryin'g out the foregoing objects it is a still further'and more specific object of my invention to provide a more durable film or coat on the walls 0t 9. metal tray and grid structure therefor which film or coat consists in the neighborhood of 60% Carnauba wax and of a rubber addition compound the latter ingredient having a chlorinated constituent which polarlzes with the metal tray or grid walls and forms a I molecular bond therewith.

- my invention embodied therein;

Fig. 2 is a longitudinal vertical sectional view of the tray and grid disclosed in Fig. 1 and is taken on the line 2--2 thereof and Fig. 3 is an enlarged sectional view of one of the webs or partitions of the grid structure illustrating a coating applied thereover in accordance with the invention.

Referring to the drawing, for illustrating my invention, I have shown in Figs. 1 and 2 thereof a metal ice tray I0 having upstanding and out- 5 wardly converging walls ll defining a relatively shallow pan-like member adapted to receive a removable metal grid structure or mold member l2. The metal tray i0 and mold or grid l2, em-

ployed to divide the interior of the tray into a 10 plurality of open-top ice block cells or compartments, may be of any desired form or construction but are preferably constructed in accordance with the tray and grid structure disclosed in the copending application of Donald H. Reeves, 16 Serial No. 98,213 filed August 2'7, 1936. The grid structure in the present disclosure therefore comprises a plurality of transverse walls It that are movable relative to a longitudinal partition or wall i5 by movement of a lever l6 pivotally 20 attached to the grid to break the ice blocks or cubes l1, frozen in the tray and grid, first from the tray l0 and thence from the grid structure l2, after separating the grid together with ice adhering thereto from the tray as fully described 25 in the copending application referred to. It is the primary purpose of my invention to improve the construction and to facilitate the operation of removing ice blocks or cubes from a tray and grid structure particularly of the type disclosed 30 in the foregoing identified copending Reeves applicatlon.

The tray I0 and walls I4 and I 5 of grid l2 in the present construction are formed from or constructed of sheet aluminum anodized or acti- 35 vated in a manner and for the purpose as set forth in the copending application of George R. Long Serial No. 127,927 filed February 26, 1937. My invention is specifically directedto the provision of a coating on anodized aluminum sur- 40 faces of ice trays and grid walls which coating is highly polar and will therefore be more readily adsorbed by the activated alumina surface.

I have found that Carnauba wax and a rubber addition substance such as chlorinated rubber 45 or rubber to which halogen derivatives have been added are compatible in most any mixture. One of these rubber addition products is known to those skilled in the art as Pliolite and is a compound produced by mixing tin chloride with (,0 rubber. The substance consisting of a mixture of Carnauba wax and a rubber addition product is a resinous material and is thermoplastic. In order to use the substance for coating ice trays and walls of grids a mixture preferably of 5:,

Carnauba wax and 40% Pliolite are dissolved in one gallon of toluol. use of Pliolite it is to be understood that any suitable chlorinated rubber addition product can be used without departing from the invention. The ice trays l and/or grids II are dipped into a mixture formed by dissolving the Pliolite and Carnauba wax in the solvent toluol. Due to the high polar characteristics of this mixture the anodized or activated alumina. surfaces of the tray and grid causes this mixture to be readily adsorbed thereby. The trays and grids are submerged in the liquid mixture for about flve minutes and are then removed and placed in an oven. The coated trays and grids are baked at a temperature of about 300 F. in order to set the film or'coat on the structures. The heating process evaporates the toluol solvent of the mixture and leaves a film or thin coat on the trays and grids consisting of Carnauba wax and "Pliolite. In addition to this film penetrating the rather porous anodized or activated surfaces of the trays and grids to. readily adhere thereto it also, by virtue of the high polar characteristics of its constituents, inherently forms a molecular bond to the trays and grids. While I havefound that a coating of a rubber addition product such as Pliolite alone does not give satisfactory results and is not permanent it is to be understood, however, that a coating consisting of Carnauba wax and Pliolite together has produced satisfactory results and is substantially permanent. This would tend to indicate that the success of a coating material does not depend entirely upon the polarization characteristics of its constituents or its water repellent characteristics but is due to both to render it substantially permanent. Thus the Carnauba wax and Pliolite in the coating material herein disclosed provides a coating for ice trays and grids which possesses both great water repellent characteristics and polarization characteristics to form a substantially permanent water repellent coating.

Thus I have discovered a coating material for metal trays and grids which is sufiiciently water repellent to improve the operation of removing ice therefrom, in accordance with the method disclosed in the heretofore identified Reeves application, and which, due to the molecular attraction of a constituent of the material with the metal of the trays or grids, substantially increases the permanency of a water repellent film or coat on the trays and grids.

I have illustrated in Fig. 3 of the drawing the metal grid or mold wall I4 and the walls of tray ID as having a coating l9 thereover provided in accordance with the present invention. It is to be understood that the entire grid structure l2 and tray I!) may be coated in the manner herein described. I do not wish to be limited to the specific proportions of Carnauba wax and rubber addition mixture to be dissolved in the toluol as other varying proportions have also been found to be somewhat satisfactory. The water repellent coating l9 on the grid walls I4 and tray Hi eliminates bonding of ice thereto and less force is necessary to actuate the ice removing lever and deformation'of these walls is prevented to thereby permit the walls to be constructed of relatively thin material thus reducing manufacturing costs.

It will be seen from the foregoing that I have provided an improved ice tray or grid or both in that I have rendered the water contacting surfaces thereof repellent to water to thereby pre- While I may prefer the,

vent bonding of ice thereto. My improved tray and grid greatly facilitates the. operation of removing ice blocks therefrom and permits the structures to be constructed of relatively thin metal because the force necessary to separate ice from the tray or grid is minimized. The highly polar characteristics of my improved coating material renders the coating substantially more permanent than the coating materials heretofore employed for the purpose herein described.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

l. A freezing device for refrigerating systems comprising a metallic tray adapted to contain water to be frozen, the metal surfaces of said tray which confine the water therein being anodized and having a water-repellent coating thereover, said coating including a mixture of vegetable wax and a halogenated rubber compound with the halogenated constituent of the compound forming highly polar molecules in said mixture which so orient themselves with respect to the anodized metal surfaces that they are strongly adsorbed thereby and render said coating substantially permanent.

2. A freezing device for refrigerating systems comprising a metallic tray adapted to contain water to be frozen, the metal surfaces of said tray which confine the water therein being anodized and having a water-repellent coating thereover, said coating including a mixture of vegetable wax and a chlorinated rubber compound with the chlorinated constituent of the compound forming highly polar molecules in said mixture which so orient themselves with respect to the anodized metal surfaces that they are strongly adsorbed thereby and render said coating substantially permanent.

3. A freezing device for refrigerating systems comprising a metallic tray adapted to contain water to be frozen, the metal surfaces of said tray which confine the water therein being anodized and having a water-repellent coating thereover, said coating including a mixture of vegetable wax and a compound having a tin chloride constituent which forms highly polar molecules in said mixture which so orient themselves with respect to the anodized metal surfaces that they are strongly adsorbed thereby and render said coating substantially permanent.

4. A freezing device for refrigerating systems comprising a metallic tray adapted to contain water to be frozen, the metal surfaces of said tray which confine the water therein being anodized and having a water-repellent coating thereover, said coating including a mixture of Carnauba wax and a rubber compound having a tin chloride constituent which forms highly polar rubber compound with the halogenated constituent of the compound forming highly Polar molecules in said mixture which so orient themselves with respect to the anodized metal surfaces that they are strongly adsorbed thereby said coating substantially permanent.

6. A freezing device for refrigerating systems comprising a metallic grid structure for disposition in a tray adapted to contain water to be frozen to thereby divide the interior of the tray 1 into a plurality of compartments, the metal surfaces of said grid structure which confine the water being anodized and having a water-repellent coating thereover, said coating including a mixture of vegetable wax and a chlorinated rubber compound with the chlorinated constituent of the compound forming highly polar molecules in said mixture which so orient themselves with respect to the anodized metal surfaces that they are strongly adsorbed thereby and render said coating substantially permanent.

'7. A freezing device for refrigerating systems comprising a metallic grid structure for disposition in a tray adapted to contain water to be frozen to thereby divide the interior of the tray into a plurality of compartments, the metal and render I surfaces of said grid structure which confine the water being anodized and having a water-repellent coating thereover, said coating including a mixture of vegetable wax and a compound having a tin chloride constituent which forms highly polar molecules in said mixture which so orient themselves with respect to the anodized metal surfaces that they are strongly adsorbed thereby and render said coating substantially permanent.

.8. A freezing device for refrigerating systems comprising a metallic grid structure for disposition in a tray adapted to contain water to be frozen to thereby divide the interior of the tray into a plurality of compartments, the metal surfaces of said grid structure which confine the water being anodized and having a water-repellent coating thereover, said coating including a mixture of Carnauba wax and a rubber compound having a tin chloride constituent which forms highly polar molecules in said mixture which so orient themselves with respect to the anodized metal surfaces that they are strongly adsorbed thereby and render said coating substantially permanent.

CHARLES E. WARING. 

